Material with variable height barbs

Abstract

A workpiece includes a material with a face and a first plurality of barbs and a second plurality of barbs extending integrally from the face. Each barb has a height above the face. The barbs of the first plurality are at least 10% higher than the barbs of the second plurality. The first plurality of barbs includes at least 10% of the barbs on the face and the second plurality of the barbs includes at least 10% of the barbs on the face. The barbs of the second plurality of barbs are bent and pointed.

1 . A workpiece comprising:
 a material with a face and a first plurality of barbs and a second plurality of barbs extending integrally from the face, each barb having a height above the face;   wherein the barbs of the first plurality are at least 10% higher than the barbs of the second plurality;   wherein the first plurality of barbs includes at least 10% of the barbs on the face and the second plurality of barbs includes at least 10% of the barbs on the face; and   wherein the barbs of the second plurality of barbs are bent and pointed.   
     
     
         2 . The workpiece of  claim 1 , wherein the first plurality of barbs includes at least 25% of the barbs on the face, and the second plurality of barbs includes at least 25% of the barbs on the face. 
     
     
         3 . The workpiece of  claim 1 , wherein the barbs of the first plurality are at least one of curved and hook-shaped. 
     
     
         4 . The workpiece of  claim 1 , wherein the height variation of the barbs forms a regular pattern. 
     
     
         5 . The workpiece of  claim 1 , wherein the material is steel. 
     
     
         6 . The workpiece of  claim 5 , wherein the workpiece is a disc brake backing plate, and the barbs are configured to receive and retain friction material. 
     
     
         7 . The workpiece of  claim 1 , wherein each barb in the first plurality of barbs is at least 25% higher than each barb in the second plurality of barbs. 
     
     
         8 . The workpiece of  claim 7 , wherein each barb in the first plurality of barbs is at least 50% higher than each barb in the second plurality of barbs. 
     
     
         9 . The workpiece of  claim 1 , wherein the first plurality of barbs includes at least 40% of the barbs on the face, and the second plurality of barbs includes at least 40% of the barbs on the face. 
     
     
         10 . The workpiece of  claim 9 , wherein each barb in the first plurality of barbs is at least 25% higher than each barb in the second plurality of barbs. 
     
     
         11 . A brake pad comprising:
 a) a disc brake backing plate comprising a steel workpiece, the steel workpiece having a face and a first plurality of barbs and a second plurality of barbs extending integrally from the face, each barb having a height above the face, wherein the height of the barbs of the first plurality is greater than the height of the barbs of the second plurality, and wherein the barbs of the second plurality of barbs are bent and pointed; and   b) a friction element secured to the steel workpiece via the barbs.   
     
     
         12 . The brake pad of  claim 11 , wherein the barbs of the first plurality are at least 10% higher than the barbs of the second plurality, and wherein the first plurality of barbs includes at least 10% of the barbs on the face, and the second plurality of barbs includes at least 10% of the barbs on the face. 
     
     
         13 . (canceled) 
     
     
         14 . (canceled) 
     
     
         15 . (canceled) 
     
     
         16 . (canceled) 
     
     
         17 . (canceled) 
     
     
         18 . (canceled) 
     
     
         19 . (canceled) 
     
     
         20 . (canceled) 
     
     
         21 . (canceled) 
     
     
         22 . (canceled) 
     
     
         23 . A method of making a workpiece, the method comprising the steps of:
 (a) gouging a face of a base workpiece of a material with a first tooth of a first geometry to create a first barb having a first height above the face; and   (b) gouging the face with a second tooth of a second geometry to create a second barb having a second height above the face that is less than the first height.   
     
     
         24 . The method of  claim 23 , further comprising repeating steps a) and b) to create a plurality of first barbs and a plurality of second barbs, wherein the plurality of second barbs includes at least 25% of a total number of barbs on the face and the barbs of the plurality of second barbs are each at least 10% lower than the barbs of the plurality of first barbs. 
     
     
         25 . The method of  claim 23 , further comprising repeating steps a) and b) to create a plurality of first barbs and a plurality of second barbs in a regular pattern. 
     
     
         26 . The method of  claim 23 , wherein the second barb is bent and pointed.